How Often Should You Equalize a Forklift Battery

The batteries of your forklift are quite expensive components and can cost between $1,500 and $5,000. It is very important to maintain the battery so that it gives long-lasting use.

With proper maintenance, your forklift battery can last for up to 5 to 6 years. And, one of the best ways to extend the life of your forklift battery is to equalize it. So, the question most forklift owners ask is, “how often should you equalize a forklift battery?”

You should equalize the charge of your forklift battery according to the schedule recommended by the battery manufacturer. How often you should equalize your forklift battery essentially depends on the age and condition of the battery. While newer batteries may have to be equalized for every 10 charging cycles, older batteries require equalization for every 5th charging cycle.

Since equalization charging is a very long charging cycle, most forklift owners equalize their forklift batteries over the weekend. However, the equalization charge and intervals depend on various factors such as the size and type of the battery, what you use it for and the hours of operation.

What Is Battery Equalization?

Equalization charging is the process when you overcharge the battery over and above the full charging cycle that is used as a remedial and maintenance activity for forklift batteries. It is essentially part of a multi-stage charging process.

Often lead-acid batteries including forklift batteries suffer from sulfation, where the sulfuric acid present in the battery cells form small crystals onto the lead plates of the battery and block that portion of the plate from the activity, thus reducing the capacity and performance of the battery.

Equalization charging is done by applying a higher voltage of 10% more than the recommended charge voltage, which helps to free the sulfur ions back into the electrolyte and desulfating it.

Equalization not only helps to remove the sulfate that has built up, but also balances the voltage of every cell in the battery when it is charged at a higher voltage than normal.

Over time, the battery acid becomes more concentrated at the bottom of the battery and the stratification of the water and acid makes it difficult for the battery to hold its charge effectively and also reduces the life of the battery.

The high voltage charge also forces up the acid, which has accumulated at the bottom of the battery to rise and mix with the water, thus reversing the stratification issue also.

So, in short, equalization charging essentially helps to remove the chemical stratification by removing the sulfate crystals from the battery plates and helps to rebalance the electrolyte concentration.

If the sulfate crystals are not removed, then it can reduce the capacity of the battery and in extreme cases, it can even make the battery completely unserviceable and useless.

How Do You Equalize a Forklift Battery

You can equalize your forklift battery by following the steps below:

  • Firstly, find a forklift battery charger that can equalize the charge of the battery by using manual voltage settings or automatically because not all chargers can equalize charge. Also, ensure that the battery and the charger are compatible and have matching voltage inputs and outputs. Once you have the proper charger, then equalization charging is a simple, straightforward process.
  • Make sure that your forklift battery is fully charged before you start to equalize it.
  • Connect the charger to your forklift battery after removing all the loads from it because overcharging the battery may cause damage to the equipment that is still connected to it.
  • Make sure that your battery charger has an equalization charging setting.
  • Set the charger to the equalization charging level as recommended by the battery manufacturer.
  • Start charging the battery and make sure that the electrolyte starts to bubble and gas.
  • Before you start the equalization process, check the specific gravity (SG) reading and only begin the process if there is a difference of 0.03 in the SG reading between the cells.
  • Measure the SG of the battery cells periodically because as the battery charges, the SG of the cells will increase. Keep monitoring this closely.
  • When the SG stops increasing, this means that the charging is finished.
  • Usually, water is lost during the charging process and so, you must replace any water that is lost.

When equalizing your forklift battery, you must make sure that you monitor the process closely and not leave the battery unsupervised. As the battery charges, it starts to overheat and hydrogen is emitted. While the production of hydrogen is normal; however, it is very flammable and if the room is not ventilated properly and the forklift battery becomes too hot, the hydrogen can explode. So, before you begin equalization charging your battery, ensure that the room is well-ventilated and cool.

How Long Does It Take to Equalize a Forklift Battery

As discussed earlier, equalizing a forklift battery is usually done after it has been fully charged. So, for the battery to be fully charged, it usually takes around 8 to 10 hours. The equalization of the battery can take up to 3 additional hours of charging.

Avoid short charging the battery during your break time or lunch break because even short charges make up a charge cycle and over time, they can affect the performance of the battery and also the battery life. You must also avoid interrupting a charge cycle—once the charge cycle begins, you should let it finish.

How Often Should You Equalize Charge Your Forklift Battery

Typically, the forklift battery should be equalized according to the recommendations by the battery manufacturer. Typically, for a 12-volt battery, you must equalize it with a voltage of at least 14.4 volts for a minimum of 1 hour once in every 10 discharge cycles. Some battery manufacturers recommend that the battery should be equalized only 2 times in a year or as and when it is required.

A good way to carry out an equalization charge is to determine how often your forklift battery is charged fully. A battery that is used often and which reaches a full charge will require equalization less frequently as compared to one that is not used frequently.

If your battery is not used often, it is recommended that it is equalized once in 6 months. If you notice that the performance of your forklift battery is reduced, this is probably a good indication that it requires an equalizing charge.

You can also decide if your forklift battery needs equalization based on the SG (specific gravity) readings of the acid present in the battery cells. If the SG varies by over 0.015 across the cells, then it is probably time to equalize.

Frequently Asked Questions

What Does Equalizing a Forklift Battery Do?

Forklift batteries must be equalized regularly because the process of equalization helps to reverse the stratification process, where the battery acid at the bottom of the battery becomes more concentrated leading to the stratification of the acid and water. When this occurs, the battery will not be able to hold its charge for a long time and this reduces the battery’s capacity.

The sulfate build-up in the battery will cause the maximum runtime of your battery to reduce, which in turn, leads to a greater number of battery replacements and more time spent charging the batteries during your work shift. Also, the forklift battery works by using several cells, which are connected in series and provide a particular voltage output.

When each of the cells of the battery has varying power outputs, this will cause a reduction in the overall battery voltage, which causes your battery to get discharged faster. All this results in increased battery replacement costs and reduced productivity. And so, equalizing your forklift battery can help to maintain the battery and prolong its life.

How Long Should You Equalize Batteries?

You should equalize your forklift batteries for around 2-4 hours at least once a month; however, you should equalize charge for a longer time if your batteries have been undercharged consistently.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.